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A large-scale detection system with more data in short time bins, small dead space and small signal identification is the ideology the scientists pursuing. These proposed demands are able to be solved by 2.5 D integration. The substance of a 2.5 D integration is called silicon interposer, which consists of the through silicon via (TSV) and redistribution layer. However, the state-of-the-art silicon interposer is not able to sustain its own mechanical strength with the detector/readout array often sitting as standalone in large science facilities and fails to reduce the expansions on the installation of the components due to its insufficient thickness and size. This study aims to propose a moderation of current interposer with large-sized, standalone properties.

This paper proposes an interposer based on double-sided silicon vias (DSSVs) interconnection. Unlike conventional interposer that is interconnected by TSVs, DSSVs interposer is interconnected by top vias (T-vias) and bottom vias (B-vias).

The fabrication process of DSSVs interposer is introduced, and the superiority of the double-sided interconnection process with two etch-stop layers is described in detail. The impact of different T-vias depth on DSSVs interconnections in the same wafer is discussed and two times PI opening processes are proposed to eliminate air bubbles in the B-via. The relationship between the interposer thickness and warpage is studied by finite element analysis simulation and experiment. The prototype of the DSSVs interposer with a size of 100  × 100 mm and a thickness of 318.2 µm is fabricated, and electrical tests including short tests and continuity tests are carried out.

This paper proposes a large-sized and stand-alone interposer based on DSSVs interconnection.

Tour guides often use humor to entertain tourists, but the process of tour guide humor (TGH) affecting tourists’ positive word of mouth (PWOM) remains unclear. To fill the gap, this study aims to investigate how TGH enhances tourists’ PWOM through perceived relationship investment, perceived wellness value and trust in tour guides.

A comprehensive mediation model was proposed based on social exchange theory (SET). Data were obtained from 335 tour group tourists and analyzed using structural equation modeling.

Results present that TGH positively predicts tourists’ PWOM. Perceived relationship investment, perceived wellness value and trust in tour guides not only play mediating roles between TGH and tourists’ PWOM, respectively, but also jointly provide two sequential mediation paths (TGH → perceived relationship investment → trust in tour guides → tourists’ PWOM and TGH → perceived wellness value → trust in tour guides → tourists’ PWOM).

The findings have practical value for tour guides and travel agencies to use TGH to improve tourists’ PWOM.

The major contribution is that a reciprocity-based framework rooted in SET was proposed to parse the complex process of TGH promoting tourists’ PWOM. Furthermore, this study enriches current knowledge by confirming that perceived wellness value is not only available in wellness tourism but can be experienced from TGH in mass tourism.

The paper aims to improve the radiation-proof capability of the self-designed mobile robot with a 7-DOF manipulator, enabling the long-playing inspection and intervention under high-dose radiation environment. In this context, gamma-ray irradiation test for electronic components and specific hardness design have also been specifically presented and discussed.

The study’s hardness design mainly focuses on shielding protection, distance protection and time protection. Irradiation test is first carried out to investigate irradiation resistance of each electronic module. Then, modular deployment and shielding calculation are completed for the point-type nuclear accidents, respectively, to achieve a robust anti-radiation design scheme. Finally, the field experiment is conducted to validate system effectiveness and good mobility, and operational practices are acquired for the realization of time protection.

Coupled with modular redeployment and shielding design, irradiation results illustrate the effectiveness of robotic anti-radiation design. Meanwhile, experiences and reformed measures from the field exercise implement efficient operation and radiological time protection.

Considering the huge risks of high-dose source exposure, the radiation-resistance of the overall system cannot be verified in the field experiment. Fortunately, irradiation test and modular shielding calculation are conducted as a minimal validation.

The proposed anti-radiation design methods and the irradiated results can be applied to many other nuclear vehicles and manipulators for the feasible multi-layer protection and excellent mobility.

A nuclear intervention robot with specific hardness design is presented in detail in this paper. Enlightened by the idea of shielding and distance protection, a large number of electronic modules with multiple types and structures are treated and compared in irradiation experiments, while modular redeployment and retrofitting are completed to reduce irradiated damages. To achieve the effect of time protection, mobility performance and operational practices are discussed and validated in the field experiment based on the mobile system.

For most companies, growth measures such as asset growth are positively correlated with accrual measures. Just like investment in fixed assets, current accrual represents one form of investment and is an integral part of a firm’s business growth. This makes it difficult to distinguish between the growth-based and earnings quality-based interpretations of the accrual effects, because high accruals can represent both high growth and inflated earnings. The purpose of this paper is to add to the literature by examining an issue that has not received much attention: the correlation between asset growth and accruals and its implication on stock return predictability. The authors address the issue using Fama and Macbeth’s (1973) cross-sectional regressions that are conditional on the correlations between the two variables.

The authors partition firms based on whether the correlation between current accrual and asset growth in the past five years is positive (ρ+) or negative (ρ−). The authors refer to these two types of firms such as “positive correlation” and “negative correlation” groups. For both groups, the authors examine whether firms with higher asset growth and higher accruals are associated with lower future stock returns. The authors implement Fama and MacBeth’s cross-sectional regressions incorporating the effect of correlations between growth and accrual measures. In addition, the authors regress hedge portfolio returns on Fama and French (1993) three-factor and Fama and French (2015) five-factor models to see if the intercepts (a’s) from these regressions are significantly different from 0.

For each year, the authors partition firms based on whether the correlation between asset growth and current accrual is positive or negative. For both the “positive correlation” and “negative correlation” firms, the authors examine the association between accruals and future stock returns. The authors find that accruals remain strong in predicting future stock returns for both groups. The accrual effects from the “negative correlation” group cannot be attributed to the growth-based hypothesis because for these firms, when accruals are high, growth measures tend to be relatively low and vice versa. The effects are most likely driven by the alternative hypothesis that investors overvalue the accrual part of earnings.

There exist a few issues when investors actually implement these strategies. These include liquidity costs, institutional holdings and short sale constraints. Lesmond (2008) concludes that the bulk of the trading profits is derived from the short side of the trade, but that this position suffers from high liquidity costs that reduces institutional holdings with consequent short sale constraints. The net gains after taking into account these issues remain an open question be addressed in the future.

The empirical results indicate that investors can do an implementable portfolio strategy of going long for a year on an initially equally weighted lowest asset growth (accrual) decile portfolio and going short for a year on an initially equally weighted highest asset growth (accrual) decile portfolio, which produces significant abnormal returns. The results further show that these abnormal returns can be improved if investors classify stocks into “the positive correlation” and “negative correlation” groups and implement trading similar trading strategies.

The empirical evidence finds that firm-year observations that exhibit a negative correlation between growth and accrual measures represents a significant 30 percent of the total firm-year observations during the sample period from July 1974 to June 2017. This highlights the necessity to undertake a detailed analysis on the issue. The authors continue to find accrual effects among these groups of firms. Therefore, the accrual effect cannot be attributed to the diminishing marginal return hypothesis. This is the main contribution of the paper.